Rail gripper



Patented Aug. ll, i925.,

ERNST EISCHER, 0F NEDER-SCHONHAUSEN, NEAR BERLN, GERIJIANY, SSIGIIOR TO THE FIRM BERLINER ACTIEN-GESELLSCHAFT FR EISENGIESSEREI UND IVIASCEIINENFABRIKATION, F CHARLOTTENBURG, GERIWANY. v

RAIL GRIPPER.

Application filed April 2,

To all 107mm t may concern.; y

Be it knownthat l[,"hl1;Ns'r Fisoiinn, en-` gineer, a citizen et Germany, residing at S Carowerstrasse, Niederschonhausen, near Berlin, Ger-mamy, have invented certain new and useful Improvements in ltail Crrippers, of which the following is a specification.

rlhis invention relates in general to rail grippers and more particularly te devices ot this kind comprising a tongs.

In the operation oit travelling cranes, doors ot sheds, halls and the like accidents have often happened on account ot' the fact that the travelling or sliding structure was not sufliciently secured against shitting due to sudden blasts oilwind etc. ln cases in which safety devices in the shape oit rail grippers or rail seizing tongs were provided, that are closed and opened by a screw spindle provided with lett .hand and right hand screw threads, the closing operation of the tongs generally required considerable time and power. rlfhese arrangements do not operate with certainty so as to hold the struct-ure against movement, because in the case ot strong blasts of wind the jaws of the tongs that engage with the rails are apt to slip on the latter.

Safety devices for locking such structures against movement caused by sudden external impulses have also been provided in which an eccentric clamping action is employed to anchor the travelling crane or the like to the rails when a movement is imparted to the crane by undesired external impulses such as a blast o1 wind. l'n these devices an eXcentric is employed by which the anchoring or locking action is secured only in one direction et travel so that to secure the desired efect in both directions two separate excentr'cs or clamping or locking members are necessary. As these excentrics co-operate with sheet metal members that embrace the rail heads and are attached to the ends of the crane the resulting satety device is of considerable length.

In order to remove these drawbacks the rail gripper in accordance with the invention comprises a tongs each ot whose jaws are provided with an exceutric that act in both directions of travel oil the crane, the arms of the tongs being moved so as to close or apply the jaws to the rail by means of a screw spindle provided with a right hand 1924. Serial No. 703,831.

and lett hand thread. By this means a simple anchoring ydevice which locks the travelling structure, such as a crane or the like, with certainty in both directions ot travel and which does not subject the rails to unfavorable stresses, is obtained.

The rail gripping tongs which are attached to the travelling structure, may be arranged in a vertical, horizontal or oblique position.

The invention is shown by ple in the drawing.

Figs. l and 2 being two different side views and F ig. 3 a horizontal-section on a line running partly through a pivot and partly through a jaw of the rail gripping tongs.

The arms a of the tongs are pivoted by pivots l; in side plates c on which a pull is exerted when the jaws of the tongs seize the rail.. The upper ends ot the arms a are forked and nuts e are arranged between the prongs so as to oscillate on pivots F. The nut e in one arm has a right handed thread while thenut in the other arm has a lett handed thread. rlhese threads take the right and left handed male screws of a spindle d. rlhe spindle threads are low pitched so that the nuts are self-locking. By turning the spindle, as by means of a sprocket wheel G, the forked ends of the arms may be moved apart or towards each other so as to open or close the jaws, or to apply the latter to the sides ot the rail head or to cause them to disengage the same. rlhe tongs or rail gripper is mounted in the travelling structure such as crane or the like, that is to be secured against movement by external impulses. lWhenever the travelling structure is to be sate-guarded against undesirable mevements the jaws et the tongs are closed suiiiciently to bring the excentrics L, journalled byA pivots c' in the jaws, into contact with the sides ot the rails. This is effected by means ot the sprocket wheel g. Any movement of the crane subsequent to the application o the excentric It results in rotation of the excentrics h about their pivots i so that the exccntrics 7L exercise a clamping action which increases as the eX- centrics It are turned away from their middle position.

Attached to the jaws are springs 7c which, when the tongs are opened, move both jaws way of examaway from the sides of the rail head and ensure symmetrical positions of both jaws with respect to the rail. The ends of the springs may be provided with rolls Z.

I claim A rail gripper comprising` a tongs provided with jaws, Self-locking means for moving the arms of the tongs so as to apply the jaws to the sides of the rail and to lock them in their applied `positions,a pivot pin in each of the said jaws, eccentrics rotatably mounted on both of the said pivot pins and exercising an increasing clamping action when turned away from their middle position in either direction, and U-shaped fiat metal springs arranged with their legs at either' Side o'l each of the said eccentrics and adapted to contact with the said eccentrics when they are rotated out of their middle position.

In testimony whereof I aiiix my signature 20 in presence of two witnesses.

ERNST FISCHER.

Vitnesses Dr. HANS ZIMMERMANN, GUs'rAv WITTENHAUZEN. 

